8.16 External Interfaces
This section describes the external interfaces supported by the CC3135MOD module, as follows:
• SPI Host
• Host UART
• External Flash
8.16.1 SPI Host Interface
The device interfaces to an external host using the SPI. The CC3135MOD module can interrupt the host using
the HOST_INTR line to initiate the data transfer over the interface. The SPI host interface can work up to a
speed of 20 MHz.
shows the SPI host interface.
HOST_SPI_CLK
HOST_SPI_nCS
HOST_SPI_MISO
HOST_SPI_MOSI
HOST_INTR
nHIB
SPI_CLK
SPI_nCS
SPI_MISO
SPI_MOSI
INTR
GPIO
CC3135MOD (slave)
MCU
Figure 8-8. SPI Host Interface
lists the SPI host interface pins.
Table 8-9. SPI Host Interface
PIN NAME
DESCRIPTION
HOST_SPI_CLK
Clock (up to 20 MHz) from MCU host to CC3135MOD module
HOST_SPI_nCS
CS (active low) signal from MCU host to CC3135MOD module
HOST_SPI_MOSI
Data from MCU host to CC3135MOD module
HOST_INTR
Interrupt from CC3135MOD module to MCU host
HOST_SPI_MISO
Data from CC3135MOD module to MCU host
nHIB
Active-low signal that commands the CC3135MOD module to enter hibernate mode (lowest power state)
shows the host SPI timing diagram.
T2
T6
T7
T9
CLK
MISO
MOSI
T8
Figure 8-9. Host SPI Timing
SWRS225D – FEBRUARY 2019 – REVISED MAY 2021
Copyright © 2021 Texas Instruments Incorporated
29